Mechanical actuator interface system for robotic surgical tools

ABSTRACT

Robotic surgical tools, systems, and methods for preparing for and performing robotic surgery include a memory mounted on the tool. The memory can perform a number of functions when the tool is loaded on the tool manipulator: first, the memory can provide a signal verifying that the tool is compatible with that particular robotic system. Secondly, the tool memory may identify the tool-type to the robotic system so that the robotic system can reconfigure its programming. Thirdly, the memory of the tool may indicate tool-specific information, including measured calibration offsets indicating misalignment of the tool drive system, tool life data, or the like. This information may be stored in a read only memory (ROM), or in a nonvolatile memory which can be written to only a single time. The invention further provides improved engagement structures for coupling robotic surgical tools with manipulator structures.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a continuation application of Ser. No. 09/418,726,filed Oct. 15, 1999, and in turn also claims priority to U.S.Provisional Patent Appl. No. 60/111,713 filed on Dec. 8, 1998. Thisapplication also claims the priority of the following co-pending UnitedStates patent applications:

Ser. No. 09/398,958, filed Sep. 17, 1999 entitled “Surgical Tools ForUse In Minimally Invasive Telesurgical Applications”;

No. 60/116,844 filed on Jan. 22, 1999, entitled “Surgical Tools For UseIn Minimally Invasive Telesurgical Applications”;

Ser. No. 29/097,544 filed on Dec. 8, 1998, entitled “Portion Of AnInterface For A Medical Instrument”;

Ser. No. 29/097,552 filed on Dec. 8, 1998, entitled “Interface For AMedical Instrument”;

Ser. No. 29/097,550 filed on Dec. 8, 1998, entitled “Portion Of AnAdaptor For A Medical Instrument”; and

Ser. No. 29/097,551 filed on Dec. 8, 1998, entitled “Adaptor For AMedical Instrument”;

The entirety of each of the above referenced applications is hereinincorporated by reference.

BACKGROUND OF THE INVENTION

This invention relates to robotically assisted surgery, and moreparticularly provides surgical tools having improved mechanical and/ordata interface capabilities to enhance the safety, accuracy, and speedof minimally invasive and other robotically enhanced surgicalprocedures.

In robotically assisted surgery, the surgeon typically operates a mastercontroller to remotely control the motion of surgical instruments at thesurgical site. The controller may be separated from the patient by asignificant distance (e.g., across the operating room, in a differentroom, or in a completely different building than the patient).Alternatively, a controller may be positioned quite near the patient inthe operating room. Regardless, the controller will typically includeone or more hand input devices (such as joysticks, exoskeletol gloves,master manipulators, or the like) which are coupled by a servo mechanismto the surgical instrument. More specifically, servo motors move amanipulator or “slave” supporting the surgical instrument based on thesurgeon's manipulation of the hand input devices. During an operation,the surgeon may employ, via the robotic surgery system, a variety ofsurgical instruments such as tissue graspers, needle drivers,electrosurgical cautery probes, etc. Each of these structures performsfunctions for the surgeon, for example, holding or driving a needle,grasping a blood vessel, or dissecting, cauterizing, or coagulatingtissue.

This new method of performing robotic surgery has, of course, createdmany new challenges. One such challenge is that a surgeon will typicallyemploy a significant number of different surgical instruments duringeach surgical procedure. The number of independent surgical manipulatorswill often be limited due to space constraints and cost. Additionally,patient trauma can generally be reduced by eliminating the number oftools used at any given time. More specifically, in minimally invasiveprocedures, the number of entry ports into a patient is generallylimited because of space constraints, as well as a desire to avoidunnecessary incisions in the patient. Hence, a number of differentsurgical instruments will typically be introduced through the sametrocar sleeve into the abdomen during, for example, laparoscopicprocedures. Likewise, in open surgery, there is typically not enoughroom adjacent the surgical site to position more than a few surgicalmanipulators, particularly where each manipulator/tool combination has arelatively large range of motion. As a result, a number of surgicalinstruments will often be attached and detached from a single instrumentholder of a manipulator during an operation.

Published PCT application WO98/25666, filed on Dec. 10, 1997 andassigned to the present assignee (the full disclosure of which isincorporated herein by reference) describes a MulticomponentTelepresence System and Method which significantly improves the safetyand speed with which robotic surgical tools can be removed and replacedduring a surgical procedure. While this represents a significantadvancement of the art, as is often true, still further improvementswould be desirable. In particular, each tool change which occurs duringa surgical procedure increases the overall surgery time. While stillfurther improvements in the mechanical tool/manipulator interface mayhelp reduce a portion of this tool change time, work in connection withthe present invention has shown that the mechanical removal andreplacement of the tool may represent only one portion of the totalinterruption for a tool change. U.S. Pat. No. 5,400,267 describes amemory feature for electrically powered medical equipment, and is alsoincorporated herein by reference.

As more and more different surgical tools are provided for use with arobotic system, the differences between the tool structures (and theinteraction between the tool and the other components of the roboticsystem) become more pronounced. Many of these surgical tools will haveone or more degrees of motion between the surgical end effectors and theproximal interface which engages the tool to the holder of themanipulator. The desired and/or practicable ranges of motion for anelectrosurgical scalpel may be significantly different than those of aclip applier, for example. Work in connection with the present inventionhas found that even after a tool is properly placed on the surgicalmanipulator, the time involved in reconfiguring the robotic system totake advantage of a different tool, and to perfect the mastercontroller's effective control over the degrees of motion of the tool,may add significantly to the total tool change delay.

In light of the above, it would be desirable to provide improved roboticsurgery tools, systems, and method. It would further be desirable toprovide techniques for reducing the total delay associated with eachtool change. It would be especially desirable if these enhanced, andoften more rapid, robotic tool change techniques resulted in stillfurther improvement in the safety and reliability of these promisingsurgical systems.

SUMMARY OF THE INVENTION

The present invention generally provides improved robotic surgicaldevices, systems, and methods for preparing for and performing roboticsurgery. The robotic tools of the present invention will often make useof a memory structure mounted on a tool, manipulator arm, or movablesupport structure. The memory can, for example, perform a number ofimportant functions when a tool is loaded on the tool manipulator:first, the memory can provide a signal verifying that the tool iscompatible with that particular robotic system. Secondly, the toolmemory may identify the tool-type (whether it is a scalpel, needlegrasper, jaws, scissors, clip applier, electrocautery blade, or thelike) to the robotic system so that the robotic system can reconfigureits programming to take full advantage of the tools' specializedcapabilities. This tool-type data may simply be an identification signalreferencing further data in a look-up table of the robotic system.Alternatively, the tool-type signal provided by the tool may define thetool characteristics in sufficient detail to allow reconfiguration ofthe robotic programming without having to resort to an external table.Thirdly, the memory of the tool may indicate tool-specific information,including (for example) measured calibration offsets indicatingmisalignment between the tool drive system and the tool end effectorelements, tool life data (such as the number of times the tool has beenloaded onto a surgical system, the number of surgical proceduresperformed with the tool, and/or the total time the tools has been used),or the like. The information may be stored in some form of non-volatilememory such as one-time programmable EPROM, Flash EPROM, EEPROM,battery-backed-up SRAM, or similar memory technology where data can beupdated and retained in either a serial or random access method, or withany of a wide variety of alternative hardware, firmware, or software.The invention further provides improved engagement structures forcoupling robotic surgical tools with manipulator structures.

In a first aspect, the invention provides a robotic surgical tool foruse in a robotic surgical system. The robotic surgical system has aprocessor which directs movement of a tool holder. The tool comprises aprobe having a proximal end and a distal end. A surgical end effector isdisposed adjacent the distal end of the probe. An interface is disposedadjacent to the proximal end of the probe. The interface can bereleasably coupled with the tool holder. Circuitry is mounted on theprobe. The circuitry defines a signal for transmitting to the processorso as to indicate compatibility of the tool with the system.

The tool will often comprise a surgical instrument suitable formanipulating tissue, an endoscope or other image capture device, or thelike. Preferably, the signal will comprise unique tool identifier data.The processor of the robotic surgical system may include programming tomanipulate the tool identifier according to a pre-determined function oralgorithm so as to derive verification data. The signal transmitted tothe processor will often include the verification data. Alternativecompatibility signals may include a signal which is listed in a tableaccessible to the processor, an arbitrary compatibility data string, orthe like.

In another aspect, the invention provides a robotic surgical componentfor use in a robotic surgical system having a processor and a componentholder. The component comprises a component body having an interfacemountable to the component holder. The body supports a surgical endeffector, and a drive system is coupled to the body for moving the endeffector per commands from the processor. Circuitry is mounted on thebody and defines a signal for transmitting to the processor. The signalmay indicate compatibility of the component with the system, may definea component type of the component, may indicate coupling of thecomponent to the system, and/or may indicate calibration of thecomponent. Typically, the component will comprise a surgical tool, amanipulator arm, a pre-positioning linkage supporting the manipulatorarm, or the like.

In another aspect, the invention provides a method for installing arobotic surgical component in a robotic surgical system. The methodcomprises mounting the component to a component holder. A signal istransmitted from the component to a processor of the robotic surgicalsystem. The component is articulated in response to the signal percommands of the processor.

In many embodiments, compatibility of the component with the roboticsurgical system will be verified using the signal transmitted from thecomponent to the processor. This can be accomplished by providing uniqueidentification data on the component, and deriving verification datafrom the identification data according to an algorithm. The verificationdata is stored with a memory of the component, the signal transmitted tothe processor including both the identification and verification data.The algorithm may then be performed on the transmitted uniqueidentification data with the processor, and the results compared withthe verification data. Advantageously, this method can take advantage ofunique identification data which is often unalterably stored in a memoryof commercially available integrated circuits.

In another aspect, the invention provides a robotic surgical tool foruse in robotic surgical systems having a processor. The tool comprises ashaft having a proximal end and a distal end. A surgical end effector isdisposed adjacent the distal end of the shaft. The end effector has aplurality of degrees of motion relative to the proximal end. Aninterface is disposed adjacent the proximal end of the shaft. Theinterface can be releasably coupled with a robotic probe holder. Theinterface comprises a plurality of driven elements. A plurality of tooldrive systems couple the driven elements to the degrees of motion of theend effector. The tool drive system has calibration offsets between anominal relative position of the end effector and the driven elements,and a measured relative position of the end effector and drivenelements. A memory stores data indicating the offsets. The memory iscoupled to the interface so as to transmit the offsets to the processor.

In yet another aspect, the invention provides a robotic surgical systemcomprising a plurality of tools of different tool-types. Each toolcomprises an elongate shaft with a cross-section suitable forintroduction into an internal surgical site within a patient body via aminimally invasive opening. A distal surgical end effector is coupled tothe shaft by at least one joint. The joint is drivingly coupled to aproximal interface by a tool drive system. Circuitry of the tooltransmits a tool-type via the interface. The tool types may optionallydiffer in at least one characteristic such as joint geometry, endeffector geometry, drive system characteristics, end effector or drivesystem strength, or the like. The system also includes a roboticmanipulator including a linkage supporting a tool holder. The toolholder releasably receives the interface. A manipulator drive motordrivingly engages the linkage so as to move the tool holder relative tothe opening and position the shaft within the surgical site. A tooldrive motor is coupled to the tool holder so as to drivingly engage thetool drive system and articulate the joint. A processor is coupled tothe tool holder. The processor has programming that effects a desiredmovement of the end effector by transmitting drive signals to the tooldrive motors of the manipulator. The processor reconfigures the programfor the different joint geometries based on the tool-type signals.

In another aspect, the invention provides a robotic surgical systemcomprising a surgical tool having a surgical end effector and aninterface. A manipulator assembly has a base and a tool holder forreleasably engaging the interface. A plurality of tool engagementsensors are coupled to the tool holder. Each tool sensor produces asignal when the interface engages the holder. A processor is coupled tothe tool engagement sensors. The processor has a tool change mode and atissue manipulation mode. The processor requires tool signals from eachof the sensors before changing the tool change mode to the tissuemanipulation mode. The processor remains in the tissue manipulation modewhen at least one, but not all, of the tool signals is lost.

The tools used in robotic surgery will be subjected to significantstructural stress during use. The stress may result in temporary loss ofan engagement signal from an engagement sensor. By providing at leasttwo, and preferably three engagement sensors, the surgical procedure cancontinue safely with the loss of an engagement signal from an individualsensor so long as the system can still verify proper engagement betweenthe manipulator and tool. This arrangement results in a robust toolengagement sensing system that avoids frequent delays during thesurgical procedure as might occur from the loss of an individual signal.

In yet another aspect, the invention provides a robotic surgical systemcomprising a manipulator assembly having a base and tool holder whichmoves relative to the base. The tool holder has a plurality of driveelements. A sterile drape covers at least a portion of the manipulator.A sterile tool has a proximal interface and distal end effector. Thedistal end effector has a plurality of degrees of motion relative to theproximal interface. The degrees of motion are coupled to drive elementsof the interface. An adapter is disposed adjacent the sterile drapebetween the holder and the interface. The adapter comprises a pluralityof movable bodies. Each movable body has a first surface driven by thedrive elements of the holder, and a second surface driving the drivenelements of the tool.

In yet another aspect, the invention provides a robotic surgical toolfor use with a robotic manipulator having a tool holder. The tool holderhas magnetically actuatable circuitry. The tool comprises a probe havinga proximal end and a distal end. A surgical end effector is disposedadjacent the distal end of the probe. An interface adjacent the proximalend of the probe is releasably coupleable with the holder. The interfacecomprises a magnet positioned so as to actuate the circuitry of theholder.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a robotic surgical procedure in which a surgeon at amaster station directs movement of robotic surgical tools effected by aslave manipulator, and shows an assistant preparing to change a toolmounted to a tool holder of the slave.

FIG. 2 is a perspective view of a robotic surgical arm cart system inwhich a series of passive set-up joints support robotically actuatedmanipulators (typically, the center arm would support a camera).

FIG. 2A is a perspective view of a robotic surgical manipulator for usein the cart system of FIG. 2.

FIGS. 2B and C are side and front views, respectively, of the linkage ofthe robotic manipulator of FIG. 2, showing how the manipulator maintainsa remote center of rotation along a shaft of the surgical tool.

FIGS. 3 and 3A are perspective views of exemplary cart structures withpositioning linkages which support the robotic manipulators in thesystem of FIG. 2.

FIG. 4 is a perspective view of an exemplary tool according to theprinciples of the present invention.

FIGS. 4A and B are schematic views of alternative drive systems for thetool of FIG. 4.

FIGS. 5A through H are illustrations of a variety of surgical endeffectors of differing tool-types.

FIG. 6 illustrates the mechanical and electrical interface of the toolof FIG. 4.

FIGS. 7A through E illustrate an adapter for coupling the interface ofFIG. 6 to the surgical manipulator.

FIGS. 7F through I illustrate the adapter of FIGS. 7A through E mountedto a holder or carriage of the manipulator.

FIGS. 7J through M illustrate the holder, its driving elements, and itselectrical contacts.

FIG. 8 is a wiring diagram for the tool of FIG. 4, the adapter of FIG.7A-E, and related components of the robotic system.

FIGS. 8A and B are rear and front views of the master console,respectively.

FIG. 9 is a functional block diagram schematically illustrating thesignal path hardware of the tool change system.

FIG. 10 is a schematic diagram illustrating the interaction between thesoftware modules related to tool change.

FIG. 11 is a logic flow chart illustrating an exemplary method forsensing engagement of a tool with the manipulator.

FIG. 12 is a flow diagram illustrating how the tool engagement signalsare used to change the operating state of the robotic system.

FIG. 13 illustrates the tool engagement method steps initiated by theprocessor in response to a change in operating state during toolchanges.

FIGS. 14A through C illustrate mounting of the adapter of FIGS. 7Athrough E to a manipulator arm, and of mounting the tool of FIG. 4 ontothe adapter.

FIG. 15 schematically illustrates an exemplary tool compatibilityverification algorithm according to the principles of the presentinvention.

DESCRIPTION OF THE SPECIFIC EMBODIMENTS

The present invention provides robotic surgery systems, devices, andmethods. Robotic surgery will generally involve the use of multiplerobotic arms. One or more of the robotic arms will often support asurgical tool which may be articulated (such as jaws, scissors,graspers, needle holders, microdissectors, staple appliers, tackers,suction/irrigation tools, clip appliers, or the like) or non-articulated(such as cutting blades, cautery probes, irrigators, catheters, suctionorifices, or the like). One or more of the robotic arms will often beused to support one or more surgical image capture devices such as anendoscope (which may be any of the variety of structures such as alaparoscope, an arthroscope, a hysteroscope, or the like), oroptionally, some other imaging modality (such as ultrasound,fluoroscopy, magnetic resonance imaging, or the like). Typically, therobotic arms will support at least two surgical tools corresponding tothe two hands of a surgeon and one optical image capture device.

The present invention will find application in a variety of surgicalprocedures. The most immediate applications will be to improve existingminimally invasive surgical procedures, such as coronary artery bypassgrafting and mitral and aortic valve repair and/or replacement. Theinvention will also have applications for surgical procedures which aredifficult to perform using existing minimally invasive techniques, suchas Nissen Fundoplications. Additionally, it is anticipated that thesesurgical systems will find uses in entirely new surgeries that would bedifficult and/or impossible to perform using traditionally open or knownminimally invasive techniques. For example, by synchronizing themovements of the image capture device and/or surgical tools with atissue undergoing physiological movement (such a beating heart), themoving tissue may be accurately manipulated and treated without haltingthe physiological movement. Additional potential applications includevascular surgery (such as for the repair of thoracic and abdominalaneurysms), general and digestive surgeries (such as cholecystectomy,inguinale hernia repair, colon resection, and the like), gynecology (forfertility procedures, hysterectomies, and the like), and a wide varietyof alternative procedures.

Referring now to FIG. 1, the robotic surgical system 10 generallyincludes master controller 150 and a robotic arm slave cart 50. Mastercontroller 150 generally includes master controllers (not shown) whichare grasped by the surgeon and manipulated in space while the surgeonviews the procedure views a stereo display. The master controllers aremanual input devices which preferably move with six degrees of freedom,and which often further have an actuatable handle for actuating tools(for example, for closing grasping saws, applying an electricalpotential to an electrode, or the like). In this embodiment, the mastercontrol station 150 also includes a processor, as will be described inmore detail hereinbelow.

Robotic arm cart 50 is positioned adjacent to patient body P and movestools having shafts. The shafts extend into an internal surgical sitewithin the patient body via openings O. As illustrated in FIG. 1, one ormore assistant may be present during surgery to assist the surgeon,particularly during removal and replacement of tools. Robotic surgerysystems and methods are further described in co-pending U.S. patentapplication Ser. No. 08/975,617, filed Nov. 21, 1997, the fulldisclosure of which is incorporated herein by reference.

Robotic arm cart 50 is shown in isolation in FIG. 2. Cart 50 includes abase 52 from which three surgical tools 54 are supported. Morespecifically, tools 54 are each supported by a series of manuallyarticulatable linkages, generally referred to as set-up joints 56, and arobotic manipulator 58. It should be noted that these structures arehere illustrated with protective covers extending over much of therobotic linkage. It should be understood that these protective coversare optional, and may be limited in size or entirely eliminated in someembodiments to minimize the inertia that is manipulated by the servomechanism, to limit the volume of moving components so as to avoidcollisions, and to limit the overall weight of cart 50.

Cart 50 will generally have dimensions suitable for transporting thecart between operating rooms. The cart will typically fit throughstandard operating room doors and onto standard hospital elevators. Thecart should have a weight and wheel (or other transportation) systemthat allows the cart to be positioned adjacent an operating table by asingle attendant. The cart should have sufficient stability in thetransport configuration to avoid tipping at minor discontinuities of thefloor, and to easily withstand overturning moments that will be imposedat the ends of the robotic arms during use.

Referring now to FIGS. 2A-C, robotic manipulators 58 preferably includea linkage 62 that constrains movement of tool 54. More specifically,linkage 62 includes rigid links coupled together by rotational joints ina parallelogram arrangement so that tool 54 rotates around a point inspace 64, as more filly described in issued U.S. Pat. No. 5,817,084, thefull disclosure of which is incorporated herein by reference. Theparallelogram arrangement constrains rotation to pivoting about an axis64 a, sometimes called the pitch axis. The links supporting theparallelogram linkage are pivotally mounted to set-up joints 56 so thattool 54 further rotates about an axis 64 b, sometimes called the yawaxis. The pitch and yaw axes intersect at the remote center 64, which isaligned along a shaft 66 of tool 54.

Tool 54 has still further driven degrees of freedom as supported bymanipulator 58, including sliding motion of the tool along insertionaxis 64 (the axis of shaft 66), sometimes referred to as insertion. Astool 54 slides along axis 64 c relative to manipulator 58, remote center64 remains fixed relative to base 68 of manipulator 58. Hence, theentire manipulator is generally moved to re-position remote center 64.

Linkage 62 of manipulator 58 is driven by a series of motors 70. Thesemotors actively move linkage 62 in response to commands from aprocessor. Motors 70 are further coupled to tool 54 so as to rotate thetool about axis 66, and often to articulate a wrist at the distal end ofthe tool about at least one, and often two, degrees of freedom.Additionally, motors 70 can be used to actuate an articulatable endeffector of the tool for grasping tissues in the jaws of a forceps orthe like. Motors 70 may be coupled to at least some of the joints oftool 54 using cables, as more fully described in U.S. Pat. No.5,792,135, the full disclosure of which is also incorporated herein byreference. As described in that reference, the manipulator will ofteninclude flexible members for transferring motion from the drivecomponents to the surgical tool. For endoscopic procedures, manipulator58 will often include a cannula 72. Cannula 72 supports tool 54,allowing the tool to rotate and move axially through the central bore ofthe cannula.

As described above, manipulator 58 is generally supported by passiveset-up joints 56. Exemplary set-up joint structures are illustrated inFIG. 3. The exemplary set-up joint system includes three types ofstructures. First, a vertical column 80 supports vertically slidingjoints 82 that are used to position manipulator 58 along the vertical orZ axis. Second, rotary joints 84 separated by rigid links 86 are used tohorizontally position manipulators 58 in the X-Y plane. Third, anotherseries of rotary joints 84 mounted adjacent a manipulator interface 88rotationally orients the manipulators.

The structure of column 80, vertical sliding joints 82, and base 52 canbe understood with reference to FIG. 3. Beginning with base 52, the basewill generally distribute the weight of the robotic structures and theforces imposed on the robotic arms. Column 80 extends upward from base52, and may optionally comprise a box steel structure. Sliding joints 82are counterbalanced by weights mounted with column 80. Sensors(typically in the form of potentiometers) indicate vertical position ofslider joints 82, and also indicate the rotational position of eachrotary joint 84. As the structure of the joint elements is known, theprocessor can accurately determine the position and orientation of themanipulator base. As the position of the tool and tool end effector willbe known relative to the manipulator base, the processor can furtheraccurately determine end effector position and orientation, as well ashow to effect movement in a desired direction by articulating one ormore the driven joints.

Each of rotational joints 84 and slider joints 82 includes a brake. Thebrake prevents articulation about the joint unless the brake isreleased, the brake being normally on. The brakes at all the joints areactuated in unison by a button on the set-up joints, thereby allowingthe operating room personnel to position the manipulator in space whenthe brake is released. Additional rotational joints similarly allow theorientation of the manipulator to be set while the brake is released.The exemplary set-up joint structure is more fully described inco-pending application Ser. No. 09/368,309, filed Aug. 3, 1999, the fulldisclosure of which is incorporated herein by reference.

An alternative set-up joint structure is illustrated in FIG. 3A. In thisembodiment, an endoscope 55 is supported by an alternative manipulatorstructure 58′ between two tissue manipulation tools. It should beunderstood that the present invention may incorporate a wide variety ofalternative robotic structures, including those described in U.S. Pat.No. 5,878,193, the full disclosure of which is incorporated herein byreference. Additionally, while the data communication between a roboticcomponent and the processor of the robotic surgical system is primarilydescribed herein with reference to communication between tool 54 and theprocessor of the robotic surgical system, it should be understood thatsimilar communication may take place between circuitry of a manipulator,a set-up joint, an endoscope or other image capture device, or the like,and the processor of the robotic surgical system for componentcompatibility verification, component-type identification, componentcalibration (such as off-set or the like) communication, confirmation ofcoupling of the component to the robotic surgical system, or the like.

An exemplary tool 54 is illustrated more clearly in FIG. 4. Tool 54generally includes a rigid shaft 102 having a proximal end 104 anddistal end 106. A proximal housing 108 includes an interface 110 whichmechanically and electrically couples tool 54 to the manipulator. Asurgical end effector 112 is coupled to shaft 102 by a wrist joint 114providing at least 1 degree of freedom, and ideally providing at least 2degrees of freedom.

As illustrated in FIG. 4A, a drive system 116 mechanically couples firstand second end effector elements 112 a, 112 b to driven elements 118 ofinterface 110. Drive system 116 is more fully described in U.S. Pat. No.5,792,135, the full disclosure of which is incorporated herein byreference. Stated simply, the drive system translates mechanical inputsfrom driven elements 118 into articulation of the wrist about first andsecond axes A1, A2, as well as into actuation of the two element endeffector by relative movement of the end effector elements about axisA2. In addition, driven elements 118 can effect rotation of the endeffector about the axis of shaft 102 (A3) by rotating the shaft relativeto proximal housing 108, and allowing the cables to twist (within alimited angular range) within the shaft.

A wide variety of alternative drive systems might be employed, includingalternative cabling arrangements, drive chains or belts, hydraulic drivesystems, gear trains, or the like. In some of these drive systems,motion of end effector 112 about the axes may be coupled to multipledriven elements 118. In other embodiments, there may be a one to onecorrespondence between driven elements 118 and motion of an end effectorelement about an axis. Still other embodiments may require fewer (ormore) driven elements to effect the desired degrees of freedom, forexample, when a single element end effector is provided. Hence,manipulation of the end effector via interface 110 will generallyinvolve some reconfiguration of the robotic system during the toolchange. One alternative drive system 116′ is shown in FIG. 4B.

Exemplary wrist structures and surgical end effectors are illustrated inmore detail in FIGS. 5A and 5B. A Potts scissor is illustrated in FIG.5A, while a 15 degree scalpel electrically coupled to a conductor 120for electrosurgery is illustrated in FIG. 5B. These different tool-typeshave wrists 114 which may have differing separation distances betweentheir axes A1, A2, differing range of motions about each axes, differentjoint binding positions or singularities, and/or other differences intheir axial geometries. Additionally, these two different end effectorstructures will have different strengths, different inertias, differenteffective gearing ratios between motion about their axes and movement ofdriven elements 118, and the like. Still further differences betweenthese two tool-types, and/or between either of these tools and tools ofother types, include the presence or absence of an electrosurgicalcapability, the useful life of the tool (in time, procedures, or toolchange operations), the ability to replace end effector elements, andthe like. It should be understood that alternative wrist jointarrangements are possible.

Still further end effectors for additional different tool-types areillustrated in 5C-5H. FIG. 5C illustrates a DeBakey forceps, while FIG.5D illustrates a microforceps. Potts scissors are again illustrated inFIG. 5E, and a clip applier is illustrated in FIG. 5F. Another scalpelis illustrated in FIG. 5G, while FIG. 5H illustrates an electrocauteryprobe. It should be understood that a wide variety of alternative endeffectors for differing tool-types may be provided, and that several ofthese tool-types may be used during a single surgical procedure. Hence,the tools of the present invention may incorporate any of theillustrated end effectors, or any other end effector which is useful forsurgery, particularly at an internal surgical site.

Interface 110 of a proximal housing 108 is illustrated in FIG. 6. Asseen schematically in FIG. 4A, driven elements 118 provide mechanicalcoupling of the end effector to drive motors mounted to the manipulator.Driven elements 118 each include a pair of pins 122 extending from asurface of the driven element. An inner pin 122A is closer to an axis ofrotation of each driven elements 118 than an outer pin 122B, which helpsto ensure positive angular alignment of the driven element. Interface110 further includes an array of electrical connecting pins 124 coupledto a memory structure 126 by a circuit board within housing 108. In theexemplary embodiment, memory 126 comprises Dallas part No. DS 2505.

Surgical tools 54 will generally be sterile structures, often beingsterilizable and/or being provided in hermetically sealed packages foruse. In contrast, the complex servo mechanism of cart 50 and manipulator58 may be difficult and/or impossible to fully sterilize betweenprocedures. Instead, a sterile drape will often cover at least a portionof the cart and manipulator structures to maintain the sterileenvironment around the patient.

As tools 54 will be removed and replaced repeatedly during manyprocedures, the tool holder could potentially be exposed tocontamination if the interface directly engages the tool holder. Toavoid contamination of the tool holder and possible cross contaminationbetween patients, the present invention provides an adaptor for couplinginterface 110 to the tool holder of the manipulator assembly.

White interface 110 is described herein with reference to mechanical,electrical, and magnetic coupling elements, it should be understood thata wide variety of telemetry modalities might be used, includinginfrared, inductive coupling, or the like.

Referring to FIGS. 7A-7E, adaptor 128 generally includes a tool side 130and a holder side 132. A plurality of rotatable bodies 134 are mountedto a floating plate 136 which has a limited range of movement relativeto the surrounding adaptor structure normal to the major surfaces of theadaptor. Axial movement of the floating plate helps decouple therotatable bodies from the tool when the levers along the sides ofhousing 108 are actuated (See FIG. 4).

Rotatable bodies 134 are resiliently mounted to floating plate 136 byresilient radial members which extend into a circumferential indentationabout the rotatable bodies. The rotatable bodies can move axiallyrelative to plate 136 by deflection of these resilient structures.

When disposed in a first axial position (toward tool side 132) therotatable bodies are free to rotate without angular limitation. However,as the rotatable bodies move axially toward tool side 130, tabs 138(extending radially from the rotatable bodies) laterally engage detentson the floating plates so as to limit angular rotation of the rotatablebodies about their axes. This limited rotation can be used to helpdrivingly engage the rotatable bodies with drive pins of the holder, asthe drive pins will push the rotatable bodies into the limited rotationposition until the pins are aligned with (and slide into) openings 140.

Openings 140 on the tool side 130 and holder side 132 of rotatablebodies 134 are configured to accurately align the driven elements 118 ofthe tool with the drive elements of the holder. As described aboveregarding inner and outer pins 122A, 122B of driven elements 118, theopenings 140 in each side of each rotatable body are at differingdistances from the axis of rotation so as to ensure that the alignmentis not 180° from its intended position. Additionally, each of theopenings 140 is slightly radially elongate so as to fittingly receivethe pins in the circumferential orientation. This allows the pins toslide radially within the openings and accommodate some axialmisalignment between the tool and holder, while minimizing any angularmisalignment and backlash between the drive and driven elements.Openings 140 on the tool side 132 are offset by about 90° from theopenings on the holder side, as can be seen most clearly in FIG. 7C.

Holder side of adaptor 128 includes another array of electricalconnector pins 124, and the tool side 132 of the adaptor includes slots142 for receiving the pin array from the tool (as illustrated in FIG.6). In addition to transmitting electrical signals between the tool andholder, at least some of these electrical connections are coupled to anadaptor memory device 144 by a circuit board of the adaptor. A latch 145releasably affixes the adaptor to the holder. A lip on the tool side 130of adaptor 128 slidably receives laterally extending tabs of housing 108adjacent to interface 110. The interaction between pins 122 and openings140 helps restrain the tool in the engaged position until the leversalong the sides of the tool housing push the floating plate axially fromthe interface so as to release the tool. The holder 129 and driveelements 119 are shown (without the adjacent manipulator structure) inFIGS. 7F through M.

Referring now to FIG. 8, an exemplary circuit diagram illustrates thecoupling of tool memory 126 and adaptor memory 144 to the wiring harnessof the manipulator. The electrically coupling of tool memory 126 withthe wiring of the manipulator may be used to sense the presence of thetool. Similarly, electrical coupling between the manipulator wiringsystem and adaptor memory 144 may be used as an adaptor engagementsensor. In the exemplary embodiment, two additional sensors are alsoprovided to determine engagement of the tool and holder: a magnetic reedswitch 147 (actuated by a magnet 125 of interface 110), and a electricalcoupling short 148 (or alternatively an end-of-life indicator)electrically coupling two of the pins 124 of tool 54. The use of amagnetically actuated sensor mounted to the holder or adapter isparticularly advantageous. The tool-mounted magnet will tend to maintainthe signal from a magnetic sensor (despite small, stress inducedmovements of the tool), in part because of the magnetic field effectsand/or hysteresis, once contact has been made. Optionally, adaptermemory 144 may be read only when no tool is coupled to the adapter by“shorting” the adapter memory with the magnetic reed switch, so that theadapter is transparent to tool/processor communications afterinstallation is completed.

An exemplary surgeon's workstation is illustrated in FIGS. 8A and 8B.Control station 150 includes processors 152 for the robotic circlemechanism. Also included in controller station 150 are a stereo imagingsystem 154 and a pair of controllers (not shown).

The surgeon will generally manipulate tissues using the robotic systemby moving the controllers within a three dimensional controller workspace of controller station 150. Processor 152 can calculate an imagecapture coordinate system via the sensors in setup joints 56 andmanipulator 58 supporting the laparoscope, and can perform coordinatesystem transformations so as to generate signals to the drive motors ofthe manipulator that maintain alignment between the three dimensionalimage of the end effectors and the hand controllers within thecontroller work space. By maintaining this alignment, as the physicianmoves the hand controller in both position and orientation, the roboticsurgery system allows the surgeon to manipulate the surgical tools as ifthe handle in the surgeon's hand and the end effector in the surgeon'sfield of view define a single contiguous surgical instrument. Thisprovides an enhanced sense of presence and allows the surgeon to operateefficiently and accurately without performing mental coordinatetransformations. The program instructions for effecting these processesmay optionally be embodied in a machine readable code stored on atangible media 153, which may comprise an optical disk, a magnetic disk,a magnetic tape, a bar code, EEPROM, or the like. Alternatively,programming instructions may be transmitted to and from processor 152using data communications systems such as an IO cable, an intranet, theinternet, or the like. An exemplary control system is described in moredetail in co-pending U.S. patent application Ser. No. 09/373,678, filedAug. 13, 1999, for a Camera Referenced Cartesian Control System, thefull disclosure of which is incorporated herein by reference.

The tool/adaptor hardware signal path is schematically illustrated inFIG. 9. Processor 152 of master control station 150 comprises multipleseparate processor boards supported by a chassis. In the exemplaryembodiment, a control and transform processor CTP handles calculation ofthe coordinate system transforms for generating the proper instructionsignals to send to servo motors. The control and transform processor CTPmay comprise an Analog Device ADSP 21060 digital signal processor, or awide variety of alternative commercially available processors. A masterdiagnostic controller MDC monitors and verifies the health of theprocessing and servo mechanical system. In the exemplary embodiment, themaster diagnostic controller MDC comprises a Dallas DS 87C530 processor.A Dallas DS 87C520 processor is used as the user interface mastercontroller UMC to handle the input and output to and from the surgeonseated at the console. Once again, these functions may alternatively beperformed by a variety of commercially available processors. Hence,processor 152 may include a single processor, or a number of distinctprocessor structures coupled together, ideally in a distributedprocessing arrangement.

In the exemplary distributed processing arrangement shown in FIG. 9,processor 152 makes use of a remote printed circuit assembly (“PCA”)referred to as the remote interface adaptor RIA, which is coupled to thechassis by a wiring harness. A remote interface adaptor RIA is providedfor each of the robotic arms of the system, typically including one PCAfor the endoscope and two PCA's for the two surgical end effectors. Theremote interface adaptor RIA also comprises a Dallas DS 87C520 processorand couples the processor 152 to the holder or carriage of manipulator58. The RIAs 56 perform local processing for the manipulators, set-upjoints, and/or tools, and communicate with processor 152 using ahigh-level language. Manipulator 58 is, in turn, coupled to tool 54 byadaptor 128 as described above.

It should be noted that reed switch 147 may actually be mounted oncarriage of manipulator 58, and may be actuated by a magnet mounted onthe tool 54. Hence, reed switch 147 ensures that tool 54 is positionedin the holder of manipulator 58, the reed switch acting as a toolsensor. Electrical coupling of the tool memory 126 and an electricalloop-back circuit 149 connecting pins of tool 54 each act as additionalindependent tool sensors. Optionally, an end-of-use detector such as alow resistance timed fuse, or the like, may change an electricalcharacteristic of the loop-back circuit to disqualify tools past the endof their safe lives. An expired tool may provide an indication to thesystem operator such as a pop-up flag, a color-change spot, or the like,to indicate the tool is at or near the end of its life. Optionally, aportable life indication device may be coupled to the tools before eachprocedure to determine if the tool has sufficient life to be used forthe planned procedure.

A variety of alternative end of use indication systems might be providedto indicate that a tool is near or at the end of its useful life. Forexample a mechanical end of use indicator may be mounted in housing 108,such as a colored button or tab which can pivot into view through anindication window of the housing. Such a button might be biased towardthe viewable position, and initially held out of sight by a latch. Thelatch might be releasable by an actuator mounted to the carriage ofmanipulator 58, for example, by the movement of a plunger of a solenoidon the manipulator. The sterile adapter or drape will preferablyaccommodate movement of such a plunger while maintaining sterileseparation between the manipulator and tool. In general, providing amechanical indicator on the tool for actuation by an actuation means ofthe manipulator can avoid the cost for end of use actuators mounted oneach tool.

Referring now to FIG. 10, the flow of the tool signals from the toolsensors during a tool change operation originates from the interactionbetween the remote interface adaptor RIA and the tool itself. The toolsignals are transmitted per procedure management/data handlerprogramming running on the master diagnostic controller MDC. The overalllogic flow proceeds according to a supervisor program running on theuser interface master control UMC according to the surgeon's input fromthe master console.

The supervisor directs the state of the robotic arms, and also perfectscoupling between a mounted tool 54 and the holder of a manipulator bydriving the servo motors in a predetermined manner, as shall beexplained below. The supervisor software directs movement of the toolthrough a middleman program running on the control and transformprocessor CTP. The middleman program accepts instructions from thesupervisor to move the surgical end effectors in the desired direction,for example, and calculates the drive signals to be provided to theservo motors so as to effect that desired motion. In other words, themiddleman program transforms the workstation space instruction into ajoint space servo signal set for the servo motors to drive the endeffectors.

It should be understood that the coordinate transformations used by themiddleman to calculate the required servo signals will vary as therelationship between the field of view from the endoscope and thesurgical end effectors varies. Deriving these coordinate transformationsis well described in the patent literature, for example, in U.S. Pat.No. 5,696,837 and U.S. patent application Ser. No. 09/373,678, the fulldisclosures of which are incorporated herein by reference. In thecontrol method illustrated in FIG. 10, a Kernel program running on thecontrol and transform processor CTP and Compute Engine processors CE'sderives these transformations based on the information provided by theposition sensors at the setup joints, manipulators, and the like.

Referring now to FIGS. 11 and 12, processor 152 changes the operatingstate of the robotic system based on tool signals from the three toolengagement sensors (reed switch 147, tool memory 126, and end of use/pinshort circuit 148) and an adaptor signal sensed by coupling with theadaptor memory 144. In the local tool detection procedure illustrated inFIG. 11 (which is performed at the remote interface adapter RIA with acycle time of 35 milliseconds) the reed switch and adapter memory arefirst sensed to check for the presence of the adapter. So long as theadapter is present, the system then checks for the presence of the toolbased on coupling with the tool memory 126. The presence or absence ofthe tool is verified by checking for the end of use or pin short circuit148 of the tool breadboard. The remote interface adapter RIA transmitsthe sensed signals from the sensor scan to the master digital controllerMDC for use by the Procedure Management/Data Handler software.

As can be understood with reference to FIG. 12, if the sterile adapteris not sensed (either upon start up or while the tool is removed), therobotic system remains in a sterile adapter off operating state S1. Oncethe sensor scan indicates that adapter 128 is present, programmanagement data handler advances the operating state to a secondoperating state S2 in which the system is awaiting engagement ofinterface 110 with the holder of the manipulator. If the signal from theadapter memory chip is lost for more than half a second, the systemreturns to the adapter off state S1.

If at least one signal from the three tool sensors indicates engagementof the tool, the operating state advances to a Tool Being Inserted modeS4, and upon agreement of all three sensors that the tool is fullymounted on the holder, the system enters a Tool Is On operating state S5in which manipulation of the end effectors by the surgeon may beenabled.

The elongate shafts of tool 54 can induce significant mechanicalstresses between interface 110, adapter 128, and the holder of themanipulator. As a result, one or more of the tool signals may be lost atleast temporarily. If tissue manipulation were halted each time a toolsignal were lost, the operation would be significantly delayed and totalrisk to the patient would increase. The present system takes advantageof the redundant tool signals by keeping the system in the Tool Is Onoperating state S5 despite the loss of one or even two tool signals. Ifthe loss of signal persists for more than a threshold time, the signalloss is stored for diagnostic purposes. Nonetheless, the system remainsin the operating state, until all three tool signals indicate the toolis removed, at which point the system drops down to the Tool Is Outoperating state S2. This procedure provides a much more robust approachthan analyzing each tool signal independently.

Referring now to FIG. 13, the instructions generated by the supervisorsoftware running on the user interface master controller UMC as a resultof the changes in state during a tool change procedure will generallyfollow one of four paths. If the adapter is not present and a tool hasbeen taken off (or no tool and adapter are present at start up), thesupervisor notifies the user, for example, by displaying an icon on thestereo display and/or assistance monitor, per path PA. If an adapter hasbeen mounted to the holder and no tool is engaged, the supervisorinitiates manipulations of the driving elements of the holder whichperfect mechanical coupling of the rotational bodies of adapter 128 withthe driving elements of the holder per path PB.

As described in some detail with reference to FIGS. 7A through E,rotatable bodies 134 can move axially relative to a floating plate 136.Prior to perfecting mechanical coupling between the holder driveelements and the rotatable bodies, pins of driving elements (which aresimilar in configuration to the driven elements 118 of interface 110)will push the rotatable bodies away from holder side 132 of adapter 128and toward tool side 130. In this rotationally limited axial position,tabs 138 of rotatable bodies 134 engage detents of the floating plate soas to prevent rotation of more than about 90°. This can ensure that thepins of the driving elements rotate relative to the rotatable bodies bydriving the servo motors of the manipulator by more than 90°.

In the exemplary tool change engagement path PB, the servo motors of themanipulator are driven from a starting central position so as to rotatethe drive elements by 180° in a first direction (for example, clockwise)in step ENGAGESA1. As the pins of the driving elements will only enteropening 140 of rotatable bodies 134 in a single angular orientation, itis possible that this step will be insufficient to perfect mechanicalcoupling. To ensure that coupling is complete, the supervisor thereforeinitiates rotation of the servo motors so as to turn the driving theelements by 360° in the opposite direction (in our example,counterclockwise) in step ENGAGESA2. At some point during the above twosteps, pins 122 of the driving elements will be aligned with openings144 of rotatable bodies 134 and the openings will receive the pins,thereby allowing the rotatable body to move axially to the freelyrotatable position. The driving elements in rotatable bodies are thencentered in their range of angular travel in step ENGAGESA3.

Once the steps of path PB have been performed so as to perfectmechanical coupling of the driving elements of the holder with therotatable bodies of the adapter 128, the supervisor directs the systemto perform the procedure outlined by the second part of path PB.Basically, the driving elements (and rotatable bodies) are centered andcentering is verified in preparation for mounting of a tool to theholder by rotating the servos right to their end of travel, left, andthen halfway between under steps TOOLPREPl, 2, and 3, respectively.These centering and verification steps are also performed if a tool hasbeen removed from the holder, per path PC.

In the final alternative procedure which will be described withreference to FIG. 13, mounting of a tool on the adapter and holderresults in the steps outlined in path PD. First, the system verifiesthat the tool is of the type which is allowable for use on thisparticular robotic surgical system. To determine compatibility,circuitry of the tool may send a signal indicating the tool-type toprocessor 152. More specifically, data stored in tool memory 148 may betransmitted to the processor. In the exemplary embodiment, the data fromthe tool memory will include a character string indicating toolcompatibility with the robotic system. Additionally, the data from thetool memory will often include a tool-type. In some embodiments, thedata will also include tool offset calibration information. This datamay be provided from the tool memory 148 in response to a request signalfrom the processor 152. A simplified version of path PD is performed ifa camera is changed, as shown.

Tool-type data will generally indicate what kind of tool has beenattached in a tool change operation. For example, the tool-type datamight indicate that Potts scissors or a scalpel has been attached to theholder. The tool-type data may include information on wrist axisgeometries, tool strengths, grip force, the range of motion of eachjoint, singularities in the joint motion space, the maximum force to beapplied via driven elements 118, the tool transmission systemcharacteristics including information regarding the coupling of drivenelements 118 to articulation of an associated (or the interactingplurality of associated) joint motion, servo gains, end effectorelements speeds, and the like.

Tool-type data may optionally be stored in memory of the robotic system.The signal from the tool may comprise an identifier referencing therelevant portion of data from the look-up table. This tool-type data maybe loaded into a memory of processor 152 by the system manufacturer, thelook-up table preferably being in the form of a flash memory, EEPROM, orthe like. As each new tool-type is provided, the robotic systemmanufacturer can then revise the look-up table to accommodate the newtool-specific information. It should be recognized that the use of toolswhich are not compatible with the robotic surgery system, for example,which do not have the appropriate tool-type data in an informationtable, could result in inadequate robotic control over the end effectorby both processor 152 and the surgeon.

In addition to the tool-type data indicated by the signals from tool 54,tool specific information may be stored in the tool memory 148 forreconfiguring the programming of processor 152. For example, there willoften be some measurable misalignment or offset between and intendedrelationship between the wrist joint and end effector elements and thepositions of driven elements 118. To accommodate this misalignmentwithout degrading the accuracy of the robotic control over the endeffectors, the measured offsets may be stored in the tool memory andfactored into the transforms generated by the Kernel. Hence, the storingof such calibration information can be used to overcome minor mechanicalinconsistencies between tools of a single type. As described above, toollife and cumulative tool use information may also be stored on the toolmemory and used by the processor to determine if the tool is still safefor use. Total tool life may be measured by clock time, by procedure, bythe number of times the tool has been loaded onto a holder, and even byindividual numbers of end effector actuations. Tool life data willpreferably be stored in the memory of the tool using an irreversiblewriting process.

To perfect mechanical coupling between the driving elements of theholder (and the previously coupled rotatable bodies 134 of adapter 128),the supervisor initiates a “turn one way, turn the other way, andcenter” operation similar to that described above. To limit the range ofmotion of driven elements 118 and ensure pins 122 enter openings 140 ofadapter 128, the holder may move axially to a proximal position so thatthe end effector is disposed within cannula 72 of manipulator 58 (seeFIG. 2B). The axial positioning and rotation (turn, turn, and center) ofthe end effector are performed under steps ENGAGETOOL1-4, respectively.

The tool-type (and preferably tool-specific) data from tool memory 148and/or the look-up table is sent to the middleman and/or Kernel softwarerunning on the coordinate transformation processor CTP for driving theappropriate coordinate transformations and generating the servo drivesignals, as generally described above with reference to FIG. 10. Thesupervisor may then verify operation of the tool by manipulating the endeffector per the calculated transforms, so as to complete the steps ofpath PD.

Methods for mounting adaptor 128 (together with a sterile drape) to theholder of manipulator 58 can be understood with reference to FIGS. 14Aand B. Subsequent mounting of tool 54 to adapter 128 generally comprisesinserting the surgical end effector distally through cannula 72 andsliding interface 110 of tool 54 into engagement with a mounted adapter,as illustrated in FIG. 14C. The tool can be removed and replaced byreversing the tool mounting procedure illustrated in FIG. 14C andmounting an alternative tool in its place.

Referring now to FIG. 15, an exemplary system and method for verifyingcompatibility of a tool with a robotic surgical system makes use of aunique identification data string that is irreversibly stored on anintegrated circuit included in the circuitry of a tool or othercomponent of the robotic surgical system. Advantageously, producers ofsuch integrated circuits can include this unique identification datastring on each integrated circuit such that no two integrated circuitsinclude the same identification data. For example, Dallas DS 2505 mayinclude a unique 64 bit identification data string which differs fromthe data strings of every other circuit of that part number.

The identification data string could be downloaded directly to theprocessor and compared with a table listing all identification datastrings of circuits included in compatible tools. Such a table couldthen be updated each time additional tools were fabricated or outdatedtools were retired.

To avoid continuously updating a compatible tool table, a verificationdata string 164 may be calculated from the unique identification dataaccording to an algorithm 166. Algorithm 166 may be used as anencryption mechanism, typically using an arbitrary function which cannoteasily be determined by sampling verification data and identificationdata from a few tools. Verification data string 164 may then be storedin a memory of the tool or other robotic component during toolproduction, typically using a non-volatile memory.

When the tool having identification data 162 and verification data 164is coupled to the robotic surgical system, a signal 168 including thesedata strings may be transmitted to processor 152 as described above. Byincluding a tangible media with method steps for performing algorithm166 in a system accessible by processor 152, the processor can alsoperform the algorithm on the unique identification data so as to derivea conformation data string 170. This can be compared with theverification data, thereby confirming compatibility of the tool with therobotic system. Algorithm 166 may include any of a wide variety of knownencryption algorithms, or may be developed specifically for use in therobotic surgical system of the present invention.

The descriptions given above regarding the exemplary devices, systems,and methods of the present invention are provided by way of an example,and for clarity of understanding. A wide variety of changes,modifications, and adaptations of these specific embodiments will beobvious to those of skill in the art. Hence, the invention is limitedsolely by the following claims.

What is claimed is:
 1. A minimally invasive surgical instrumentcomprising a shaft having a working end; an end effector mountingformation positioned at the working end of the shaft and arranged to beangularly displaceable about at least two axes; elongate elementsconnected to the end effector mounting formation to cause selectivepivotal movement of the end effector mounting formation about the axesin response to selective pulling of the elongate elements; a supportbase positioned on an opposed end of the shaft; and at least threespools angularly displaceably mounted on the support base and to whichopposed ends of the elongate elements are connected so that selectiveangular displacement of the spools causes the selective pulling of theelongate elements, the spools having axes which are parallel and spacedapart relative to each other.
 2. A minimally invasive surgicalinstrument as claimed in claim 1, wherein the support base includes agenerally planar outer surface and the axes are generally perpendicularrelative to the generally planar surface.
 3. The surgical instrument ofclaim 1, wherein at least one of the spools includes a major surfacegenerally normal to the axis of the spool, the at least one spool beingrotatable about the axis.
 4. The surgical instrument of claim 3, whereinat least one of the spools includes an arcuate edge.
 5. The surgicalinstrument of claim 3, wherein at least one of the spools has a majorsurface is which is asymmetric relative to said axis.
 6. The surgicalinstrument of claim 3, wherein each of said first plurality of movablebodies is substantially similarly shaped.
 7. The surgical instrument ofclaim 1, wherein the instrument includes at least one joint disposedadjacent the shaft working end, and the at least one joint is coupled toat least one of the elongate elements, said at least elongate elementbeing housed within the shaft.
 8. The surgical instrument of claim 1,wherein at least one of the elongate elements includes a flexible cableportion.
 9. The surgical instrument of claim 1 wherein the instrumentincludes at least two end effector mounting formations.
 10. The surgicalinstrument of claim 9, wherein each of the end effector mountingformations is movable independently of the other as a result of movementof at least two of the elongate elements, each of the at least two ofthe elongate elements being engaged to one of the spools.
 11. Thesurgical instrument of claim 1, wherein at least one of said spoolsspool is engageable with a rotatable actuator body of a robotic surgicalsystem, so as to cause a rotation of the spool when the rotatable bodyof the actuator is rotated in response to the operator inputs.
 12. Thesurgical instrument of claim 11, wherein the at least one spool causesrotation of the shaft.
 13. The surgical instrument of claim 12, whereinat least three of the spools are each removably mechanically engageblewith a respective rotatable actuator body of a robotic surgical system.14. The surgical instrument of claim 13, wherein at least three of thespools are each substantially simultaneously removable from therespective rotatable actuator bodies.
 15. The surgical instrument ofclaim 13, wherein said instrument further comprises a proximal latch fordisconnecting the instrument from the rotatable actuator body of therobotic surgical system.
 16. The surgical instrument of claim 11,wherein at least three of the spools are each engageable with arespective rotatable actuator body of a robotic surgical system insubstantially the same manner of engagement.
 17. The surgical instrumentof claim 11, wherein each of the spools are engageable with a respectiverotatable actuator body of a robotic surgical system, each spoolcomprises at least one mechanical protrusion, each of the spools isremovably mechanically engageable with the respective rotatable actuatorbody via the mechanical protrusion, and wherein each of the spools ismechanically asymmetric relative the axis of the spool.
 18. The surgicalinstrument of claim 17, wherein each of the spools comprises a pluralityof mechanical protrusions, each of the spools is removably mechanicallyengageable with a respective rotatable actuator body of a roboticsurgical system via said mechanical protrusions.
 19. The surgicalinstrument of claim 11, wherein a sterile adapter is interposed betweenthe spools of said instrument and the rotatable actuator bodies of therobotic surgical system.
 20. The surgical instrument of claim 19,wherein the spools engage said sterile adapter and said sterile adapterengages said rotatable actuator body of a robotic surgical system.
 21. Amethod for performing robotic surgery, comprising: providing aninstrument removably coupleable to a robotic arm drive assembly, saidinstrument comprising proximal and distal portions, said proximalportion comprising a first plurality of movable bodies engagable with asecond plurality of corresponding movable bodies on the drive assembly,said instrument including at least one distal joint coupled to an endeffector member, at least one of said first plurality of movable bodiesbeing coupled to said distal joint by at least one drive member, andsaid drive member being housed in a shaft portion of said instrumentextending between said proximal and distal portions; coupling saidinstrument to said drive assembly by engaging the first plurality ofmovable bodies with the second plurality of movable bodies; controllingthe operation of said drive assembly from a remote location so that themovable bodies of said drive assembly rotate one or more of the movablebodies of the instrument, thereby causing the at least one distal jointsof the instrument to move; and engaging tissue with the end effectormember to perform surgery.
 22. The surgical instrument of claim 21,wherein the step of coupling said instrument to said drive assemblyincludes substantially simultaneously engaging said first plurality ofmovable bodies with said second set of movable bodies.
 23. The surgicalinstrument of claim 21, wherein the step of coupling said instrument tosaid drive assembly includes interposing a sterile adapter between saidfirst plurality of movable bodies of said instrument and said second setof movable bodies of said drive assembly.
 24. The surgical instrument ofclaim 23, wherein said first plurality of movable bodies engage saidsterile adapter and said sterile adapter engages said second set ofmovable bodies.
 25. A surgical instrument for operative mounting to arobotic surgical system, the surgical system having a drive assemblyoperatively coupled to a control unit operable by inputs from anoperator, the drive assembly having a plurality of actuator bodies whichare movable in response to operator inputs, the surgical instrumentcomprising: a proximal portion and a distal portion, the proximalportion comprising a first plurality of movable engaging interfacebodies; at least one distal end effector member; a plurality of joints,at least one of the joints being coupled to the end effector member, thejoints being coupled to the plurality of movable engaging interfacebodies by a plurality of drive members; and the instrument beingremovably coupleable to the drive assembly when the instrument isoperatively mounted to the surgical system so that the plurality ofactuator bodies engage with corresponding ones of the plurality ofinterface bodies, and so that movement of the actuator bodies inresponse to operator inputs produces a corresponding movement of atleast one of the joints.
 26. The surgical instrument of claim 25,wherein at least one interface body is a first rotatable body, at leastone actuator body is a corresponding second rotatable body, and thesecond rotatable body is engagable with the first rotatable body so asto cause a corresponding rotation of the first rotatable body when thesecond rotatable body is rotated in response to the operator inputs. 27.The surgical instrument of claim 25, wherein the instrument includes atleast a shaft portion extending between the proximal and distalportions, at least one of the joints is disposed adjacent the distalportion, and the at least one joint adjacent the distal portion iscoupled to at least one of the plurality of drive members which ishoused within the shaft portion.
 28. The surgical instrument of claim25, wherein at least one of the instrument drive members includes aflexible cable portion.
 29. The surgical instrument of claim 25, whereinthe instrument includes at least two end effector members, each endeffector member being movable independently of the other as a result ofmovement of at least two drive members, each drive member being engagedto one of the plurality of interface bodies.
 30. The surgical instrumentof claim 25, wherein one of the actuator bodies engaged on theinstrument causes rotation of the shaft portion.
 31. The roboticsurgical system of claim 25, wherein said instrument further comprisesat least a second distal end effector member.
 32. The surgicalinstrument of claim 25, wherein each of said plurality of movableinterface bodies is substantially similarly shaped.
 33. The surgicalinstrument of claim 25, wherein each of said plurality of movableinterface bodies engaging with one of said plurality of drive members.34. The surgical instrument of claim 33, wherein each of said drivemembers engaging with a respective one of said movable interface bodiesin a similar manner.
 35. The surgical instrument of claim 25, whereineach of said plurality of movable interface bodies includes an arcuateedge.
 36. The robotic surgical system of claim 25, wherein each of saidplurality of movable interface bodies includes a major surface, each ofsaid first plurality of movable bodies being rotatable about an axisnormal to its major surface.
 37. The surgical instrument of claim 36,wherein each of said plurality of movable interface bodies includes anarcuate edge, each of said plurality of movable interface bodies beingrotatable about an axis normal to its major surface, wherein each ofsaid plurality of movable interface bodies is asymmetric relative tosaid axis.
 38. The surgical instrument of claim 25, wherein each of saidplurality of movable interface bodies of said instrument removablymechanically engages with said plurality of movable actuator bodies ofsaid drive assembly.
 39. The surgical instrument of claim 38, whereineach of said plurality of movable interface bodies of said instrumentare substantially simultaneously engageable with said plurality ofmovable actuator bodies.
 40. The surgical instrument of claim 25,wherein each of said plurality of movable interface bodies of saidinstrument comprises at least one mechanical protrusion, each of saidplurality of movable interface bodies is removably mechanicallyengageable with said plurality of movable actuator bodies of said driveassembly via said mechanical protrusion, and wherein each of saidplurality of movable interface bodies is mechanically asymmetricrelative to a rotational axis of said interface body.
 41. The surgicalinstrument of claim 25, wherein each of said plurality of movableinterface bodies of said instrument comprises a plurality of mechanicalprotrusions, each of said plurality of movable interface bodies isremovably mechanically engageable with said plurality of movableactuator bodies of said drive assembly via said mechanical protrusions.42. The surgical instrument of claim 25, wherein a sterile adapter isinterposed between said plurality of movable interface bodies of saidinstrument and said plurality of movable actuator bodies of said driveassembly.
 43. The surgical instrument of claim 42, wherein saidplurality of movable interface bodies of said instrument engages saidsterile adapter and said sterile adapter engages said plurality ofmovable actuator bodies of said drive assembly.
 44. The surgicalinstrument of claim 25, wherein said instrument further comprises aproximal latch for disconnecting the instrument from said driveassembly.